Vacuum excavation uses pressurized streams of fluids to dig a hole, a pit, a trench or a trough by loosening debris material such as soil, rocks and other materials. The loosened debris-materials are then pneumatically collected and removed by a vacuum system. Vacuum excavation can expose buried facilities without the risk of damage that may arise by digging with shovels or other heavy equipment.
Typically, vacuum-excavation apparatuses are transported upon large vehicles, such as trucks. The trucks can carry liquid-pressurization or pneumatic equipment, vacuum equipment and large tanks for containing the excavated soil, rocks and other materials. Booms are typically connected to the top of the tanks to connect a vacuum hose to the tank. The boom allows the user to move an input end of the vacuum hose about the truck during excavation operations. Due to the weight of this equipment, the mass of the excavated materials and the stress loads imparted by moving the swing boom about, the tanks are typically made up of steel with ¼ inch to ½ inch thick walls. A stress load may also be referred to as a mechanical stress. Furthermore, many tanks have thick walls or further physical reinforcements, such as extension members, that are connected to the tank to accommodate the stress loads imparted upon the tank by the moving boom. In other examples of vacuum trucks, the swing boom can have a separate support-structure that connects the swing boom directly to the vacuum truck.
In order to accommodate the weight associated with the tanks and the further physical reinforcements or separate support-structure, a typical vacuum-truck has two or three rear-axles. While the trucks with multiple rear-axles can support the weight of the vacuum-excavation apparatus and can carry heavy loads of debris materials within the tank, these trucks have limited maneuverability, low fuel-efficiency and can cause damage to roadways. Furthermore, many jurisdictions require a specialized operator's license to operate trucks with multiple rear-axles.